You mean 105 seconds ;-)Yes I tried a 100% polyester tshirt at various terms and times. I did get the most success with 420 degrees (F) and 105 minutes. I still have so much ink left on the paper after I press it.
I don’t know why the majority of the ink won’t transfer. At least I got some ink to transfer…
No point going too long or too hot. That will just sublimate the ink out of the garment. 60 @400F will give you "reasonable" results, else something is wrong. WHITE. The fabric is white, right? You cannot sublimate dark garments, and even pastel garments will throw off the color balance. Sublimation can only dye the garment darker than it is; it cannot lighten it. All light and brightness must come from the original garment. Same reason copy/printer paper is white.
Show us a photo of the paper before pressing and the shirt after pressing. Sublimation ink does not look bright until it has been heated, so if the unpressed print on the paper looks bright and colorful, it isn't sublimation ink. Sub ink should look dull until heated.